In the past, techniques have been proposed such as coating a fluororesin onto a superelastic alloy wire of Ni—Ti or the like to improve the sliding characteristics of a medical wire, or using a pigment-containing fluororesin as the outermost layer of a medical wire so that physicians and the like in a treatment facility are able to identify the appropriate medical wire using only the external appearance (for example, see Japanese Published Unexamined Patent Application No. 2003-250905).
Usually in such cases, a fluororesin will exhibit superior properties only after it is baked at a temperature at or above its melting point (usually 350-400° C.). For this reason, medical guide wires coated with a fluororesin (referred to below as fluororesin-coated medical guide wires) are subjected to a final baking treatment for a period of about 1 minute in an air-circulating oven or the like where the temperature is increased to be at or above the melting point of the fluororesin (for example, see Japanese Published Unexamined Patent Application No. 2004-130123).